This invention pertains to the field of vehicle lifts for servicing an automobile and/or for diagnosing and tuning the chassis of an automobile. The invention also pertains to the field of transporting automobiles in carrier vehicles, loading and unloading automobiles into and from carrier vehicles, and otherwise handling the automobiles. Within those fields, the invention is particularly concerned with transporting racing cars and preparing them for racing, but has application to other vehicles and situations as well, for example transporting antique and classic cars and handling and servicing them at their destination.
Automobile racing is an extremely popular sport and is becoming more so. In 1998 NASCAR alone had 17 of the 20 best-attended sports events in America, each with an attendance of over 100,000 spectators. Cable television coverage of these events has greatly enlarged the audience, which is continuing to expand by millions of viewers each year. Other types of automobile racing, for example, Grand Prix road racing, drag racing, and endurance racing, are also popular throughout the world. The U.S. retail market for products made specifically for racing has been estimated at $1.5 billion annually. Equally impressive is the number of actual participants in auto racing. It was recently estimated that at least 385,000 people competed in an organized automobile race at least once in 1998.
Teams and individuals who participate in auto racing vary greatly in terms of equipment sophistication, financial and personnel resources, driver skills, and support crew proficiency. While the larger and better-financed competitors receive most of the publicity, a far greater number receive little or no publicity. For many of these participants, responding to the varied challenges presented by the competition provides much of the motivation. If a team or individual is unable to compete one way, they must be resourceful enough to devise other ways to compete, while staying within their particular limitations as well as the rules.
One of these challenges is the efficient use of time and personnel at the track. This challenge is particularly demanding during a racing event or in on-site preparation for a racing event. It is also a factor in preparation and development of the automobile and driver in order to optimize their respective performances for future racing events, since xe2x80x9ctrack timexe2x80x9d is usually limited and costly. As best stated by Carroll Smith, xe2x80x9cNothing is ever in such short supply at a race track as time. . . . There is never enough time. . . . Time lost during practice or qualifying is lost forever and time wasted during a day of testing is expensive and frustrating. Especially at one of the $1,000 per day tracksxe2x80x9d. (Tune to Win, 1978, page 161. Mr. Smith also authored Engineer to Win in 1984. Both books are incorporated herein by reference.)
Competing for track time are numerous procedures which require accessing and working on or inspecting the undercarriage of the racing car, often repeatedly and with unavoidable interruptions for test driving on the track. These procedures generally fall into three categories which are not mutually exclusive: chassis tuning, safety, and inspection.
Chassis tuning is essential, if the racing car is to even approach its maximum performance capabilities. While the car with the best chassis tuning may not always win the race, chassis tuning often determines the winner, will always determine the winner when other factors are equal, and almost always determine a loser if ignored. Examples of chassis tuning procedures are: diagnosing and correcting chassis binding; disconnecting linkages for front or rear anti-sway bars and exchanging an anti-sway bar (i.e., anti-roll bar or stabilizer bar) for one of a different torsion rate; determining that the rear end of the car is square to the chassis or at a desired offset (i.e., xe2x80x9cstringing the carxe2x80x9d), changing one or more springs, struts, or shock absorbers to ones with more desirable mechanical properties; setting the front and/or rear ride height; adjusting the front and/or rear camber to the desired degree setting; adjusting the front for camber gain and cross percentages of caster; adjusting the front and/or rear for toe-out or toe-in; adjusting for optimum bump steer; adjusting corner weights (e.g. by adjusting jack screws or wedges); adjusting for optimum Ackerman steering, if the car is so equipped; measuring and optimizing the scrub radius of tires; adjusting control devices for rear axle performance (e.g., panhard bar or Watts link); adjusting rear torque arms; adjusting other devices relative to rear axle performance (e.g., to optimize anti-squat, anti-lift, and anti-dive characteristics, rear-steering characteristics, rear camber and rear toe-in); determining optimum weight distributions on each of the car""s wheels (i.e., xe2x80x9cscaling the carxe2x80x9d). Chassis tuning frequently uses known alignment tools, for example, turn plates, caster/camber gages, toe-in devices, and devices for measuring linear distance. Chassis tuning is a process of balancing many interrelated variables to provide optimum handling characteristics and thus ultimate racing performance.
Safety procedures include the following: inspecting fasteners and tightening as necessary; inspecting for oil leaks, gas line leaks, shock absorber malfunctions and correcting as necessary; inspecting brake lines for signs of chafing or failure and correcting as necessary; inspecting brake pads and rotors and servicing as necessary; inspecting the flywheel scatter-shield device; inspecting the drive shaft safety hoop; inspecting for damage or undesirable changes resulting from a track incident.
Routine maintenance procedures include the following: changing engine oil; inspecting and/or changing transmission lubricants; inspecting and/or changing final drive lubricants; checking and maintaining the integrity of the exhaust system.
Racing cars are transported to racing events and elsewhere by a variety of means. One such means is a tractor-trailer combination in which an enclosed, two-level trailer carries at least four cars. The cars are loaded and unloaded by an elevatable horizontal platform which is supported by two sets of diagonal chains at the rear of the trailer when in use and folds against the rear of the trailer when not in use. Such transporters are depicted in Old Car Trader, July 1998, pages Y-28 and Y-29, in the advertisements of VIP Transport, Inc. and Exotic Car Transport. We believe that these particular platforms fold about two hinges, in an arrangement similar to that shown by Erlinder U.S. Pat. No. 3,675,739 on a truck.
Also known are mobile lifts for servicing or transporting automobiles. See, for example, Grimaldo U.S. Pat. No. 3,931,895, Cray U.S. Pat. No. 4,445,665, Lapiolahti U.S. Pat. No. 4,750,856, and Wellman U.S. Pat. No. 5,810,544. An example of another, commercially available lift is depicted in Hemmings Motor News, September 1999 issue, page 8879, in an advertisement by Autolifters of America, Inc., Wichita, Kans.
Stationary lifts or grease pits are rarely, if ever, available for the use of contestants at a track. There are currently several methods of elevating racing cars at tracks so that they can be worked on and inspected. One such method utilizes a lever, for example a first class lever with a long handle at one end, a load-supporting surface at the other end, and in between a fulcrum which bears on the pavement. A second method involves four pressurized gas-actuated jacks which are mounted on the racing car itself. A third method consists of jacking up one side or end of the car at a time by one or more jacks which, though having a specialized and sophisticated design, operate much the same way as ordinary garage or vehicle-carried jacks. The first two methods are fast and are often used for raising a car several inches during a race for limited purposes, for example changing tires, but are not suitable for allowing working under the car for most purposes, because of obvious space, stability, and safety limitations. The third method can raise the car somewhat higher, more so if jackstands are used, but is slower and still cannot provide the access and stability made possible by more robust conventional lifts.
Each of these methods has the further disadvantage that raising the car takes the sprung weight of the car off the suspension, so that repairs, modifications, and adjustments which affect the handling of the car must be made under artificial, xe2x80x9cno-loadxe2x80x9d conditions. Moreover, lowering the car back down does not necessarily, and probably will not, return handling-affecting parameters to a condition which allows a useful comparison with their xe2x80x9coriginal conditionxe2x80x9d that existed just prior to the raising, repair, modifying, or adjustment. Put another way, in these prior art methods the mere acts of raising and lowering change these parameters. Sometimes crew personnel bounce the car up and down while rolling it backward and forward after it has been lowered, in an effort to achieve a comparable condition. This remedy is not reliable; for example, the wheels may not be able to assume their original position without having been driven at track speed with the weight of the driver. Alternatively, the car may be driven on the track again in an attempt to achieve the desired comparable suspension condition, but this remedy involves additional time and expense and may itself introduce some further variable; for example, the suspension may reflect the most recent track condition, vehicle speed, or driver action.
Some racing teams undoubtedly employ sophisticated lifts at their permanent facilities at home, and these lifts may have some degree of mobility. We are not, however, aware of a mobile lift which has been used at a track to (1) raise the car in the horizontal position (with the exception of the on-board jacks mentioned above), (2) raise the car sufficiently high to allow its undercarriage to be worked on and inspected by a person who is not lying on the ground, or (3) raise or lower the car without unloading its suspension. If such use of a mobile lift has taken place, we suspect that the reason it was not adopted for widespread use was that the lift failed to meet one or more requirements for use at a track. These requirements, in my opinion, include a combination of at least two of the following, in no particular order: mobility, compactness, ease and speed of operation, ability to be operated by one or two people, stability, safety, ease and speed of setup and takedown, rigidity, ability to duplicate previous conditions, reliability, versatility, durability, low cost, and ability to accept racing cars which, because of their ground-effects fairing designed to come as close as possible to the surface of the track, have minimal ground clearance.
Aside from lifts, equipment for diagnosing and tuning the chassis of a racing car exists, but apparently little descriptive literature has been made available to the public. We believe that most of such equipment is large, sophisticated, and expensive, and likely to be useful only at a few permanent facilities scattered around the world. Typically such facilities are by leased to well-heeled clients for relatively short periods of time. For obvious competitive reasons both the lessors and the lessees are inclined to maintain in strict secrecy the diagnostic and tuning technology as well as the application thereof to particular racing cars and problems. We are not aware of such diagnostic equipment that is designed for use at a track or has been used at a track.
Spencer-Smith U.S. Pat. No. 6,044,696 discloses portable apparatus for testing and evaluating the performance of racing cars under simulated conditions. The automobile, without wheels and tires, is bolted to the apparatus by its wheel hubs, which of course renders it unable to include wheels or tires in any diagnosis or evaluation. This apparatus does not appear to be suited for use at a track and the patent does not disclose such use, but the apparatus is said to be useful prior to arriving at the track on or just before race day, so as to enable race teams to focus their full attention on chassis set-up after they arrive at the track. The Spencer-Smith apparatus does not have the ability to lift the automobile or permit its undercarriage to be accessed for servicing.
The invention addresses these requirements and is intended to meet them more successfully than the prior art, by meeting more of the requirements and by meeting individual requirements in a superior manner.
An object of the invention is to provide a mobile lift system which may be used at a track or other race course for servicing a racing car in a horizontal elevated position, in which position the undercarriage of the car may be comfortably and efficiently accessed through an open platform by a person who, since he or she is not required to lie on the ground, has full use of both hands and ergonomically favorable body positioning and leverage.
Another object of the invention is that the system and the racing car may be transported by road to and from the course in a single carrier vehicle, such as a truck or trailer.
Another object of the invention is that the system may be used to load and unload the racing car into and from the carrier vehicle.
Another object of the invention is that the system be capable of elevating the racing car for service in a standalone mode, in which the platform is separated from the carrier vehicle, thereby conforming to the space limitations at most race courses.
Another object of the invention is that the system allow the racing car to be driven from the ground onto the platform and vice versa.
Another object of the invention is that the platform support the racing car by its tires, so as to permit the racing car to be worked on, measured, and tested without taking the sprung weight of the car off its suspension.
Another object of the invention is to use the system to simulate, on a racing car supported by the platform, loads the car is likely to encounter on the race course. While such loads are dynamic and transient on the race course, the system may be used to replicate them and their effects in a static condition, thereby enabling the observation, measurement, comparison, and analysis of the positions and relationships of various components of the car""s suspension and steering.
The present invention is a system for handling and servicing a car that has been transported by road to a destination away from a permanent servicing facility at home. Exemplary such destinations include tracks or other race courses and shows and similar events for the transported car. The inventive system employs an open platform for supporting the car by its tires in a horizontal position. The platform supports the car in a carrier vehicle, such as a truck or trailer, when the carrier vehicle is transporting the car to the course. This eliminates the need for an additional carrier vehicle, an additional driver, and the attendant expenses. The platform and a separate tracked or wheeled crawler are used to unload the car from the carrier vehicle onto the ground and to load the car from the ground into the carrier vehicle. In addition, the platform is used at the course or other destination to elevate the car so that its undercarriage is accessible through an opening in the platform and thus may be worked on or inspected to prepare or improve the car for racing or otherwise service the car. These uses are equally well suited to vehicles other than racing cars, for example antique and classic cars being transported to shows, exhibitions, rallies, and the like.
A portion of the system according to the present invention is a lifting platform which has utility at a track irrespective of whether it is used for transporting the racing car. Such utility includes the chassis tuning, safety, and servicing procedures discussed thus far, which have corresponded to procedures which have been performed using a conventional lift to elevate a car. Beyond that, however, the inventive platform enables new procedures to be performed at a track as well as elsewhere. We call these new procedures xe2x80x9cadvanced chassis tuningxe2x80x9d or, more specifically, xe2x80x9cchassis tuning with constantly loaded suspensionxe2x80x9d. Essentially these procedures are based on the concept of substituting the elevated platform for a floor, so that chassis tuning procedures can be performed simultaneously with measuring the effects caused by the procedures. For example, weighing simultaneously the four wheels of a racing vehicle is a customary way to measure these effects. Kroll et al. U.S. Pat. No. 5,232,064 discloses portable scales for weighing wheels of racing cars, and it is known that scales of this type may be arranged in a spaced relationship in a fixture which lies on the ground. Such scales may be placed in the deck of the present invention, so that the chassis may be tuned while the car is being weighed. Individually operable legs according to the invention are intended to provide the leveling control necessary for such advanced chassis tuning. Another technique which can be used in advanced chassis tuning on the platform according to the invention is manipulating the racing car to simulate, in a static situation, the positions and loadings the car has experienced or is likely to experience on the track. This is effected by providing input forces to the chassis by a rigid link connecting the undercarriage of the car to the platform. By adjusting and accurately controlling these input forces, various, dynamic loads the car will encounter on the track can be simulated.